1. The Field of the Invention
The present invention relates to a method and device for a low light loss coupling between light emitting diode mounted in a flexible circuit and an optical fiber of either glass or plastic.
2. The Prior Art
The development of both the LED and the optical fiber has created a need for an advantageous manner for connecting these two together so as to have the maximum amount of light from the LED coupled into the optical fiber. The previous methods for accomplishing this have not proved satisfactory in that bulky devices have been required for mounting the LED and the fibers, for example, see U.S. Pat. No. 3,932,761. Also, many of the known connecting devices have only been capable of mating bundles of fibers, rather than individual fibers thereby emphasizing the size of the entire coupled device and effectively reducing the amount of information that can be transmitted by the cable. Because of the nature of both optical fibers and LEDs, these devices can fulfill an illuminating function for small tightly fitting components, if suitable means can be provided to produce an efficient light coupling connection therebetween. The use of flexible circuitry in the combination also lends itself to positioning sensors in cramped quarters with the optical fiber transmitting information to a more convenient position for observation.